Moldable sand compositions and methods for making the same

ABSTRACT

The present invention relates to moldable sand compositions, methods for making the moldable sand compositions, and methods for using the moldable sand compositions. In a particular embodiment, the moldable sand composition comprises between about 70% to about 95% sand, between about 5% to about 30% water, a polar polymeric resin, a crosslinking agent, and a humectant. In an exemplary embodiment, the composition contains no oils, waxes, glycols, or rubbers. The composition is capable of becoming hardened over time in order to maintain the achieved shape, and can be re-wetted and molded again after becoming hardened.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/790,692, filed Mar. 8, 2013, which claims the benefit of priority ofU.S. Provisional Application No. 61/622,145, filed Apr. 10, 2012, thecontents of which applications are incorporated by reference herein, intheir entireties and for all purposes.

FIELD OF THE INVENTION

The present invention relates generally to moldable compositions for useas a children's craft product, and more particularly to moldable sandcompositions that can dry and harden, and are reusable after re-wetting.

BACKGROUND OF THE INVENTION

Many different types of modeling compositions for creating figures orsculptures have been introduced over time, particularly for use as craftproducts by children, and for general artistic purposes. One of the mostconventional types of modeling composition is oil-based clay, whichremains malleable even when left for long periods in dry environments.Other modeling compositions, such as water-based starch doughs, cantypically dry and harden when left out in the open air. However,starch-based modeling compositions have a tendency to break apart duringthe molding process, and to crack after they have dried.

Moldable compositions based on sand have a grainier texture compared tothose based on clay or starch. One of the disadvantages of somesand-based compositions is that they contain components such as oil,wax, or rubber, which can produce a greasy or sticky feeling, inaddition to the risk of staining clothes or the surrounding environment.Sand-based compositions also do not typically harden, and if they doharden, they cannot be re-wetted and molded again. There remains a needfor moldable craft materials that provide the experience of playing withsand, that are suitable to be handled by children, that provide theversatility of being able to harden and maintain the achieved shape, andthat can be molded again after re-wetting.

SUMMARY OF THE INVENTION

An embodiment of the present invention provides a moldable sandcomposition comprising between about 70% to about 95% sand, betweenabout 5% to about 30% water, a polar polymeric resin, a crosslinkingagent, and a humectant. In an exemplary embodiment, the compositioncontains no oils, waxes, glycols, or rubbers.

Another embodiment of the present invention provides a method for makinga moldable sand composition comprising mixing between about 70% to about95% sand, between about 5% to about 30% water, a polar polymeric resin,a crosslinking agent, a humectant, and one or more additives. Inparticular embodiments, the composition is capable of becoming hardenedat room temperature over time in order to maintain the achieved shape,and can be re-wetted and molded again after becoming hardened.

Another embodiment of the present invention provides a method of using amoldable sand composition comprising molding the moldable compositioninto a desired shape; exposing the composition to air for a period oftime sufficient for it to become a hardened composition; adding water tothe hardened composition to make a re-wetted moldable composition; andmolding the re-wetted moldable composition, wherein the moldablecomposition comprises between about 70% to about 95% sand, between about5% to about 30% water, a polar polymeric resin, a crosslinking agent,and a humectant.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides moldable sand compositions for use bychildren and artists, particularly for use as a children's craftproduct. The compositions have a grainy texture and provide the userwith the sensation of playing with wet sand, but without the messnormally associated with sand (i.e., very little residual sand comes offof the moldable composition onto the user's hands or the surroundingenvironment). The compositions of the present invention are moldable,which means a user can manipulate the compositions into desired shapesand figures. The compositions have a hardening characteristic, whichmeans that they are initially moldable but are capable of drying andhardening if left in open air at room temperature for a period of time(i.e., left outside of any enclosure, such as a container, that wouldsubstantially prevent moisture from evaporating off of the composition),so that they maintain the achieved shape. The compositions are no longermoldable if they harden, but become moldable again after the addition ofwater. The compositions are water-based and are preferably free of oilycomponents, which means they do not leave an oily residue on the user'shands or on the surrounding environment. The compositions are alsonon-staining and are suitable for use by children. The moldable sandcompositions of the present invention have a unique sandy texture andthey are visco-elastic (i.e., they can stretch and flow), unlike othermoldable sand compounds.

According to preferred embodiments, the moldable sand composition of thepresent invention comprises sand, water, a polar polymeric resin, acrosslinking agent, and optionally a humectant and additives. Themoldable sand composition preferably comprises between about 70% toabout 95% sand and between about 5% to about 30% water. As used herein,a percentage (%) refers to a weight percentage of the composition (withthe “composition” referring to all of the components in the totalcomposition, including any components that are premixed prior to beingcombined with the rest of the components), unless indicated otherwise.Any type of sand may be used in the compositions of the presentinvention. In preferred embodiments, the most common component of thesand (and most preferably the only component) is silica sand. As usedherein, “sand” refers to either colored or non-colored sand, and mayinclude mixtures of different types of sand. The sand particles can beany shape, but in preferred embodiments most of the sand particles arespherical. Both the density and size of sand particles contribute to theunique properties of the present invention. Sand particles are largeenough to yield a rough, sandy texture to dried objects.

According to particular embodiments, the sand that is used in thecomposition is pre-colored sand, which means that the sand particles arepre-coated with a pigment dispersion to impart color, prior to the sandbeing included in the composition. In alternative embodiments, the sandis not pre-colored (i.e., it is unpigmented), so that it has a neutralcolor, such as white or tan. In those embodiments, a pigment can beadded to the moldable sand composition as an additive, preferably in theform of a pigment dry blend. For example, the pigment can be added tothe composition in an amount between about 0.01% to about 10%, betweenabout 0.01% to about 7.5%, between about 0.01% to about 5%, betweenabout 0.01% to about 3%, between about 0.01% to about 2%, or betweenabout 0.01% to about 1%. According to particular embodiments, the colorof the composition becomes more intense (brighter) as the amount ofpigment that is added to the composition increases. In theseembodiments, it has been observed that the sand particles themselves donot change color; rather, the color imparted by the pigment tends toremain mixed with the other components of the composition. According tocertain embodiments, “special effect” pigments can be used, such asfluorescent pigments, which can impart a neon effect to the composition,or phosphorescent pigments, which can impart a “glow in the dark”effect.

The sand particles of the present invention are preferably greater than150 μm in diameter, more preferably between about 150 μm to about 400 μmin diameter, and most preferably between about 200 μm to about 300 μm indiameter. Compositions of the present invention preferably comprisebetween about 70% to about 95% sand, more preferably between about 80%to about 90% sand, and most preferably between about 84% to about 88%sand. In an exemplary embodiment, a composition of the present inventioncomprises about 86% sand.

The compositions of the present invention comprise a sufficient amountof water to act as a solvent for the other components, but not so muchwater that the compositions shrink substantially after the waterevaporates. The compositions preferably maintain a high dry strengthupon hardening. In an exemplary embodiment, water is the only solvent inthe composition (i.e., the composition does not contain any othersolvents, including water-miscible solvents such as glycols). Thisprovides the beneficial characteristic that, once the compositionbecomes dry and hardened at room temperature, only water needs to beadded to the dried composition so that it becomes moldable again. Thisalso provides an advantage over moldable compositions that cannot bere-wetted and re-molded after they have hardened. In preferredembodiments, compositions of the present invention comprise betweenabout 5% to about 30% water, more preferably between about 7% to about20% water, and most preferably between about 8% to about 12% water. Inan exemplary embodiment, a composition of the present inventioncomprises about 9.5% water. The amount of water in the composition maydecrease over time as the composition is left in open air and the waterevaporates.

According to certain aspects of the invention, the sand and watertogether comprise greater than 90% of the total composition, morepreferably greater than 92% of the total composition, and mostpreferably greater than 95% of the total composition. In certainembodiments of the invention, the ratio of sand to water is betweenabout 3 to about 15, more preferably about between about 4 to about 12,and most preferably about between about 7 to about 10. In an exemplaryembodiment, a composition of the present invention comprises a ratio ofsand to water of about 9. The relative amounts of sand and water helpthe composition remain moldable while providing a high dry strength whenthe composition hardens at room temperature.

The compositions of the present invention include a polar polymericresin as a binder. According to preferred embodiments, the polarpolymeric resin is poly(vinyl alcohol) (PVA). However, other polarpolymeric resins known by those skilled in the art may also be used. Incertain embodiments, compositions of the present invention comprisebetween about 0.5% to about 3% polar polymeric resin, more preferablybetween about 0.75% to about 2.75% polar polymeric resin, and mostpreferably between about 1% to about 2% polar polymeric resin.

PVA is made by the hydrolysis of poly(vinyl acetate) and, whencommercially purchased, may be partially or fully hydrolyzed. PVA variesin molecular weight according to the length of the resin chain. In apreferred embodiment, the composition includes PVA which is partiallyhydrolyzed (about 87-89%). A particularly preferred type of PVA isCelvol® 523. In certain embodiments, compositions of the presentinvention comprise between about 0.5% to about 3% PVA, more preferablybetween about 0.75% to about 2.75% PVA, and most preferably betweenabout 1% to about 2% PVA.

The compositions of the present invention include one or morecrosslinking agents. The one or more crosslinking agents preferablycomprise a boric compound, such as boric acid or a borate salt. Boricacid is the most preferred crosslinking agent. According to alternativeembodiments, the one or more crosslinking agents may not comprise aboric compound. Non-limiting examples of such crosslinking agentsinclude titanates and zirconates (e.g., those commercially availableunder the Tyzor® tradename), dialdehydes such as glutaraldehyde,polyfunctional acids such as adipic and citric acids, polyfunctionalacid anhydrides such as trimellitic anhydride, non-monovalent cationssuch as Ca²⁺, Fe³⁺, etc. In certain embodiments, compositions of thepresent invention comprise between about 0.1% to about 0.5% crosslinkingagent(s), more preferably between about 0.15% to about 0.45%crosslinking agent(s), and most preferably between about 0.2% to about0.4% crosslinking agent(s).

In preferred embodiments, compositions of the present invention compriseone or more humectants. Humectants inhibit drying and increase theamount of time that the composition remains moldable prior to drying andbecoming hardened. A wide variety of humectant materials may beemployed. In a preferred embodiment, the composition comprises glycerinas a humectant. The composition preferably comprises between about 1% toabout 3% humectant, more preferably between about 1.25% to about 2.75%humectant, and most preferably between about 1.5% to about 2.5%humectant.

According to certain embodiments, compositions of the present inventioncomprise one or more additional additives. These additives may include,but are not limited to, pH adjusters, buffers, defoamers, dispersingagents, scents, preservatives, and/or colorants. The compositionspreferably comprise less than about 1% additives, more preferably lessthan about 0.9% additives, most preferably less than about 0.8%additives. In preferred embodiments, the compositions of the presentinvention comprise between about 0.1% to about 2% additives, morepreferably between about 0.25% to about 1.5% additives, and mostpreferably between about 0.5% to about 1% additives. Alternatively, theone or more additives may be present in larger amounts if theadditive(s) include one or more pigments for imparting color tocompositions that include sand which is not pre-colored (as discussedabove); for example, the additive(s) may be present in the compositionin an amount between about 0.01% to about 10%, between about 0.01% toabout 7.5%, between about 0.01% to about 5%, between about 0.01% toabout 3%, between about 0.01% to about 2%, or between about 0.01% toabout 1%.

Such additives are readily available from numerous sources. Common pHadjusters include phosphoric acid and triethanolamine. Defoamers, suchas Foamex® 825, can be added to eliminate air bubbles upon mixing of thecomponents. One or more preservatives, such as anti-microbial agents andfungicides, can be added to increase the shelf life of the composition.Some examples of preservatives include Kathon® LX, Nuosept® 95,Acticide® LA, and Polyphase® P100. One or more colorants, such aspigments (e.g., as discussed above with respect to pigments that may beused with sand that is not pre-colored) or dyes, may optionally be usedin the composition. A scent or fragrance may also be added to thecomposition.

According to certain aspects of the present invention, the moldable sandcomposition comprises sand, water, a polar polymeric resin, acrosslinking agent, a humectant, and one or more additives (e.g., one ormore pH adjusters, buffers, defoamers, dispersing agents, scents,preservatives, colorants, or a combination thereof). According toparticular embodiments, the moldable sand composition comprises betweenabout 70% to about 95% sand, between about 5% to about 30% water,between about 0.5% to about 3% polar polymeric resin (e.g., PVA),between about 0.1% to about 0.5% crosslinking agent, between about 1% toabout 3% humectant, and between about 0.01% to about 10% additives(e.g., between about 0.01% to about 7.5% additives, between about 0.01%to about 5% additives, between about 0.01% to about 3% additives,between about 0.01% to about 2% additives, or between about 0.01% toabout 1% additives). According to preferred embodiments, the moldablesand composition comprises between about 70% to about 95% sand, betweenabout 5% to about 30% water, between about 0.5% to about 3% polarpolymeric resin (e.g., PVA), between about 0.1% to about 0.5%crosslinking agent, between about 1% to about 3% humectant, and betweenabout 0.1% to about 2% additives. According to more preferredembodiments, the moldable sand composition comprises between about 80%to about 90% sand, between about 7% to about 20% water, between about0.75% to about 2.75% polar polymeric resin (e.g., PVA), between about0.15% to about 0.45% crosslinking agent, between about 1.25% to about2.75% humectant, and between about 0.25% to about 1.5% additives.According to most preferred embodiments, the moldable sand compositioncomprises between about 84% to about 88% sand, between about 8% to about12% water, between about 1% to about 2% polar polymeric resin (e.g.,PVA), between about 0.2% to about 0.4% crosslinking agent, between about1.5% to about 2.5% humectant, and between about 0.5% to about 1%additives. According to an exemplary embodiment, the moldable sandcomposition comprises about 86% sand, about 9.5% water, about 1.5% polarpolymeric resin (e.g., PVA), about 0.3% crosslinking agent, about 2%glycerin, and about 0.7% additives.

Advantageously, there are numerous ingredients in other commerciallyavailable moldable compositions which are not included in compositionsof the present invention. In a preferred embodiment, the compositiondoes not include any cellulose compounds, such as hydroxypropylcellulose, which could promote undesirable microbial growth. Thecomposition also preferably does not include any glycols, such aspropylene glycol. A glycol compound would be likely to impede drying andwould therefore interfere with the ability of the composition to becomehardened. In embodiments where the compositions are solely water-basedand do not include solvents such as glycols, the compositions can moreeasily harden due to water evaporation and can become moldable againafter the addition of water.

In additional preferred embodiments, the composition does not includeany oils or oily components, such as mineral oil, petroleum, paraffinoil, or silicone oil. It is also preferred that the composition does notinclude any rubbers, such as polyisobutylene, or waxes, such as siliconwax. These components commonly produce a greasy or sticky feeling, inaddition to the risk of staining clothes or the surrounding environment.They may also interfere with the ability of the composition to becomehardened, and to then become moldable again after the addition of water.

Because the composition preferably has a grainy texture, rather than asmooth texture that is characteristic of other moldable compositions, itis not necessary to coat the sand particles with an additional componentthat imparts a smooth texture rather than a grainy texture. Thus, thecomposition is preferably free of calcium carbonate, talc, aluminatrihydrate, and titanium dioxide, which are commonly added to othercommercially available products.

According to certain aspects of the present invention, the moldable sandcomposition consists of, or consists essentially of, sand, water, apolar polymeric resin, a crosslinking agent, a humectant, and one ormore additives (e.g., one or more pH adjusters, buffers, defoamers,dispersing agents, scents, preservatives, colorants, or a combinationthereof). Thus, according to certain aspects, the moldable sandcomposition is absent (i.e., contains 0%) cellulose compounds, glycols,oils, rubbers, and waxes. According to particular embodiments, themoldable sand composition consists of, or consists essentially of,between about 70% to about 95% sand, between about 5% to about 30%water, between about 0.5% to about 3% polar polymeric resin (e.g., PVA),between about 0.1% to about 0.5% crosslinking agent, between about 1% toabout 3% humectant, and between about 0.01% to about 10% additives(e.g., between about 0.01% to about 7.5% additives, between about 0.01%to about 5% additives, between about 0.01% to about 3% additives,between about 0.01% to about 2% additives, or between about 0.01% toabout 1% additives). According to certain embodiments, the moldable sandcomposition consists of, or consists essentially of, between about 70%to about 95% sand, between about 5% to about 30% water, between about0.5% to about 3% polar polymeric resin (e.g., PVA), between about 0.1%to about 0.5% crosslinking agent, between about 1% to about 3%humectant, and between about 0.1% to about 2% additives. According tomore preferred embodiments, the moldable sand composition consists of,or consists essentially of, between about 80% to about 90% sand, betweenabout 7% to about 20% water, between about 0.75% to about 2.75% polarpolymeric resin (e.g., PVA), between about 0.15% to about 0.45%crosslinking agent, between about 1.25% to about 2.75% humectant, andbetween about 0.25% to about 1.5% additives. According to most preferredembodiments, the moldable sand composition consists of, or consistsessentially of, between about 84% to about 88% sand, between about 8% toabout 12% water, between about 1% to about 2% polar polymeric resin(e.g., PVA), between about 0.2% to about 0.4% crosslinking agent,between about 1.5% to about 2.5% humectant, and between about 0.5% toabout 1% additives. According to an exemplary embodiment, the moldablesand composition consists of, or consists essentially of, about 86%sand, about 9.5% water, about 1.5% polar polymeric resin (e.g., PVA),about 0.3% crosslinking agent, about 2% glycerin, and about 0.7%additives.

A method according to the present invention comprises combining all ofthe components of the compositions described above and thoroughly mixingthem until they display a substantially uniform color, consistency, andtexture. According to certain aspects of the present invention, a methodfor making a moldable sand composition comprises mixing the componentsof the compositions described above, namely, sand, water, a polarpolymeric resin, a crosslinking agent, a humectant, and one or moreadditives (e.g., one or more pH adjusters, buffers, defoamers,dispersing agents, scents, preservatives, colorants, or a combinationthereof) in the weight percentages described above, preferably at roomtemperature (i.e., the method is preferably free of any heating steps).

According to a preferred embodiment, the components of a “polarpolymeric resin premix” (e.g., a “PVA premix”) are separately combinedand mixed together, with the premix comprising water, a humectant (e.g.,glycerin), a polar polymeric resin (e.g., PVA), and one or more optionaladditives. The premix is combined with the other components of thecomposition, namely, sand, water, a crosslinking agent, and one or moreoptional additives. All of the components are then mixed together untila substantially uniform color, consistency, and texture are achieved. Itis not necessary to heat any of the components during the process. Thus,all of the combining and mixing steps can be performed at roomtemperature (about 20° C.-about 25° C.).

The polar polymeric resin premix preferably comprises between about 5%to about 15% of the total composition, more preferably between about7.5% to about 12%, and most preferably between about 9% to about 11%. Incertain embodiments, the premix comprises between about 50% to about 75%water, more preferably between about 55% to about 70% water, and mostpreferably between about 60% to about 65% water. In certain embodiments,the premix further comprises between about 10% to about 30% humectant,more preferably between about 15% to about 25% humectant, and mostpreferably about 20% humectant. In certain embodiments, the premixfurther comprises between about 0.1% to about 10% additives, morepreferably between about 2% to about 8% additives, and most preferablybetween about 3% to about 5% additives.

A method for using a moldable sand composition of the present inventioncomprises molding the moldable sand composition into a desired shape,exposing the moldable sand composition to air (preferably ambient air atroom temperature, about 20° C.-about 25° C.) for a period of timesufficient for the moldable sand composition to become a hardenedcomposition (i.e., exposing the composition to air comprises leaving themoldable sand composition outside of any enclosure, such as a container,that would substantially prevent moisture from evaporating off of thecomposition), adding water to the hardened composition to make are-wetted moldable composition, and molding the re-wetted moldablecomposition, wherein the moldable sand composition comprises any of themoldable sand compositions described herein.

According to alternative embodiments, additional modifications may bemade to the composition after it has been molded into a desired shape.For example, the method may further comprise adding a decorative agentto the composition, either before or after it has hardened. Thedecorative agent may be selected from the group consisting of glaze,paint, glitter, shimmer, and a combination thereof. After thecomposition has hardened, the method may further comprise chiseling thehardened composition (e.g., to add texture) or further sculpting thehardened composition.

The present invention also provides kits comprising a moldable sandcomposition. According to a particular embodiment, a kit comprises amoldable sand composition in accordance with embodiments of the presentinvention, and one or more molds. The composition is preferably providedin one or more containers, such as one or more tubs. Multiple portionsof the composition can be removed from the container(s) and molded intoa multitude of desired shapes. For example, after a portion of themoldable sand composition is packed into a mold, and then removed fromthe mold, the composition preferably retains the shape of the mold. Themold(s) provided in the kit may be any shape, for example, they may bein the shape of a star, square, circle, sphere, rectangle, or actionfigure. The kit may provide molds according to a particular theme, forexample, a construction kit may comprise mold(s) in the shape of one ormore bricks or concrete blocks. According to one embodiment, after auser has molded multiple portions of the composition into the shapes ofmultiple objects (e.g., bricks), the molded objects can be stacked nextto each other and/or on top of each other to create a structure. The kitmay further comprise one or more tools or toys (e.g., one or more toycars or trucks) which can be used to mold or shape the composition,e.g., to reshape the composition after it has been molded into the shapeof the one or more molds. For example, the kit may comprise one or morerollers for flattening a molded composition (e.g., for flatteningportions of the molded composition that have been shaped into bricks).The roller(s) may be provided as part of a toy, such as a truck (e.g., aconstruction truck). The kit may also comprise one or more decorativeagents (e.g., glaze, paint, glitter, and/or shimmer).

The following examples are provided to describe the invention in greaterdetail and are intended to illustrate, not limit, the invention.

EXAMPLES Example 1

While only certain compositions are set forth below, alternativecompositions will be apparent to those skilled in the art. Such artisanswill be able to modify the compositions with an eye toward the desiredperformance properties and intended use.

The moldable sand compositions disclosed below were made by first mixingthe components of the PVA Premix provided in Table 1 at room temperature(about 21° C.).

TABLE 1 PVA Premix Component Weight Percentage Water 61.64 Glycerin20.03 Celvol ® 523 PVA 14.02 Foamex ® 825 1.00 Phosphoric Acid 0.90Nuosept ® 95 1.81 Kathon ® LX 0.60 Total 100.0

The PVA Premix was then combined at room temperature with the othercomponents of the composition, as set forth in Table 2 below.

TABLE 2 Component Weight Percentage Sand 86.2 PVA Premix 9.7 City Water3.5 Boric Acid 0.3 Triethanolamine 0.3 Total 100.0

All of the components were mixed until a uniform color, consistency, andtexture were achieved. The final composition is provided in Table 3below.

TABLE 3 Component Weight Percentage Sand 86.20 Water 9.48 Glycerin 1.94Celvol ® 523 1.36 Foamex ® 825 0.10 Phosphoric Acid 0.09 Nuosept ® 950.18 Kathon ® LX 0.06 Boric Acid 0.30 Triethanolamine 0.30 Total 100.0

Example 2

Table 4 provides data with respect to the % weight loss and hardeningcharacteristics over time for a 20 gram composition of the presentinvention under ambient conditions (70° F., 21° C., 45% relativehumidity) that had been molded into a round shape. As shown in Table 4,the composition began to harden after approximately two hours. Afterapproximately 24 hours, the composition exhibited approximately 11%weight loss and was hardened to the extent that it was no longermoldable or deformable by hand.

TABLE 4 DryTime % Weight Loss Comments 0.5 Hours 1 Moist Surface 1.5Hours 2 Dry Surface 2 Hours 3 Dry Surface - beginning to harden 4 Hours4 Continuing to harden 5 Hours 5 Continuing to harden 7 Hours 6Continuing to harden - still deforms with pressure 24 Hours 11Hardened - does not deform

Although the present invention has been described in connection withspecific embodiments, it should be understood that the invention asclaimed should not be unduly limited to such specific embodiments.Indeed, various modifications and variations of the describedcompositions and methods of the invention will be apparent to those ofordinary skill in the art and are intended to be within the scope of theappended claims.

What is claimed is:
 1. A moldable sand composition comprising sand,water, a polar polymeric resin, one or more crosslinking agents, and ahumectant, wherein a ratio of sand to water is between 7 and 15, andwherein the moldable sand composition is initially moldable, becomeshardened following exposure to air at room temperature, and becomesmoldable again following an addition of water.
 2. The composition ofclaim 1, wherein the sand comprises silica sand.
 3. The composition ofclaim 1, wherein the one or more crosslinking agents comprise a boriccompound.
 4. The composition of claim 1, wherein the one or morecrosslinking agents are selected from the group consisting of titanates,zirconates, dialdehydes, polyfunctional acids, polyfunctional acidanhydrides, non-monovalent cations and a combination thereof.
 5. Thecomposition of claim 1, wherein the humectant comprises glycerin.
 6. Thecomposition of claim 1, wherein the polar polymeric resin comprises PVA.7. The composition of claim 1 comprising between about 80% to about 90%sand.
 8. The composition of claim 1 comprising between about 7% to about20% water.
 9. The composition of claim 1 comprising between about 0.5%to about 3% polar polymeric resin.
 10. The composition of claim 1comprising between about 1% to about 3% humectant.
 11. The compositionof claim 1 further comprising one or more additives, wherein theadditives are selected from the group consisting of pH adjusters,buffers, defoamers, dispersing agents, scents, preservatives, colorants,and combinations thereof.
 12. The composition of claim 11, wherein thecomposition comprises less than about 1% of the one or more additives.13. The moldable sand composition of claim 11 comprising between about84% to about 88% sand, between about 8% to about 12% water, betweenabout 1% to about 2% polar polymeric resin, between about 0.2% to about0.4% one or more crosslinking agents, between about 1.5% to about 2.5%humectant, and between about 0.5% to about 1% additives.
 14. Thecomposition of claim 1, wherein the composition contains no oils, waxes,glycols, or rubbers.
 15. A method for making a moldable sand compositioncomprising mixing sand, water, a polar polymeric resin, one or morecrosslinking agents, a humectant, and one or more additives, wherein aratio of sand to water is between 7 and 15, and wherein the moldablesand composition is initially moldable, becomes hardened followingexposure to air at room temperature, and becomes moldable againfollowing an addition of water.
 16. The method of claim 15, wherein thecomposition comprises between about 84% to about 88% sand, between about8% to about 12% water, between about 1% to about 2% polar polymericresin, between about 0.2% to about 0.4% one or more crosslinking agents,between about 1.5% to about 2.5% humectant, and between about 0.5% toabout 1% additives.
 17. The method of claim 15, wherein the compositioncontains no oils, waxes, glycols, or rubbers.
 18. The method of claim15, wherein there is no heating step.
 19. A kit comprising: a moldablesand composition inside a container; and one or more molds, wherein themoldable sand composition comprises sand, water, a polar polymericresin, one or more crosslinking agents, and a humectant, and wherein aratio of sand to water is between 7 and 15, and wherein the moldablesand composition is initially moldable, becomes hardened followingexposure to air at room temperature, and becomes moldable againfollowing an addition of water.
 20. The kit of claim 19 furthercomprising one or more toys for molding or shaping the composition.